1. Field of the Invention
The present invention relates to a movement apparatus including a movable body reciprocating in a direction, a long member following the movable body, and a support member supporting the long member, and to an image recording apparatus.
2. Description of Related Art
As a type of image recording apparatus, there is known an inkjet recording apparatus that ejects droplets of ink based on input signals so as to record an image on a recording medium. In the inkjet recording apparatus, an actuator is disposed in a recording head in which nozzles are formed, and ink is drawn to the actuator, which is selectively and locally pressurized to eject the ink in the form of droplets from the nozzles. For instance, the actuator is constituted by an electrostrictive or piezoelectric element and the ink is pressurized by locally deflecting or deforming the actuator, or alternatively the actuator is constituted by a heating element and the ink is pressurized by locally evaporating the ink.
In an inkjet recording apparatus, the recording head is reciprocated relative to a recording medium, e.g., recording sheet. For instance, the recording head is mounted on a carriage and reciprocated therewith. The carriage receives a driving force from a motor or others and reciprocates in a direction along a guide such as a rod or a rail. While the carriage is reciprocating, the recording head selectively ejects ink droplets onto the recording medium in order that the ink droplets land on the recording medium to form an image to be recorded.
The ink is supplied to the recording head from an ink cartridge or others disposed separately from the recording head. For instance, this is realized by using an ink tube which functions as a passage through which the ink is supplied from the ink cartridge to the recording head. The ink tube has a flexibility such that the form or position or attitude of the ink tube changes in accordance with a reciprocating movement of the carriage, and has a length corresponding to a maximum distance between the carriage and the ink cartridge, i.e., the distance therebetween at the time when the carriage is at its farthest position from the ink cartridge. Hence, when the carriage is at its closest position to the ink cartridge, the ink tube is curved or bent in a substantially U-like shape or otherwise.
How ink droplets are ejected from the recording head, e.g., the timings at which ink droplets are ejected, is based on electrical signals sent from a control board or main board of the image recording apparatus. The electrical signals are transferred between the main board and a head control board, which is a control board for the recording head and is reciprocated together with the recording head. This signal transfer between the main board and the head control board is enabled by an electric cable connecting these boards. Like the ink tube, this electric cable changes its form in accordance with the reciprocating movement of the carriage.
JP-A-2007-118240 discloses a cable holding mechanism used in an inkjet recording apparatus in which a flexible cable is connected with a carriage. The cable holding mechanism includes a cable holder and a cable-holder driving belt coupled with the cable holder. While the carriage is moved or reciprocated, the cable holder is moved by the cable-holder driving belt in accordance with the reciprocating movement of the carriage in order that the flexible cable in a curved or bent state or shape does not slack.
However, the cable holding mechanism including the cable-holder driving belt and a motor or others for driving the cable-holder driving belt is relatively large in size and high in cost. Further, when the cable holder is moved, the motor, the cable-holder driving belt, and others generate operation noise, and frictional contact between the cable holder and the flexible cable causes high-frequency noise, making the overall operation noise of the movement apparatus relatively high. Still further, the frictional contact between the cable holder and the flexible cable leads to wear of the flexible cable, which may result in damage of the flexible cable or electrical disconnection in the flexible cable. In addition, minute particles produced from the worn flexible cable may inhibit the other members than the flexible cable from normally operate.